148 SHUFELDT. [Vol. XVII. 



aperture is the larger, it has, in an adult female specimen (col- 

 lected at Aker, Nov. 10, 1876), a height of 25 mm. and a width 

 of 12-13 mm. ; the entrance is smaller upon the left side, and 

 has a height of 22 mm, and a width of 11-12 mm. Compara- 

 tively speaking, they are situated rather high up, inasmuch as 

 their lower extremities do not fall below the inferior arc of the 

 eyeball, upon either side. Superiorly, the right opening passes 

 above the eyeball ; the left being situated a little lower down 

 than this. The distal border of an ear-opening is bounded by 

 a thickened integument, approaching in its nature a low, free 

 fold of skin. The ear-flaps are also asymmetrical. On the 

 right side, where the aperture is the larger, it is broad, being 

 squarely truncated both superiorly and inferiorly, and has an 

 average width of about 12 mm. ; on the left side the flap nar- 

 rows as it ascends, but below is carried out as an irregular, 

 inferiorly directed point ; in this locality the flap sees its great- 

 est breadth, being about 1 1-12 mm. The nostrils are markedly 

 small, elevated, and almost circular; their diameter, in either 

 case, being about 2 mm. The cranium, which is symmetrical, 

 is comparatively large, and the posterior region is prettily 

 dome-shaped ; its greatest vertical height being comparatively 

 far forwards, that is to say, about over the middle of the orbits. 

 The beak is of medium size, with flattened sides ; the mandi- 

 bles, measured from the frontal bones, not taking into consid- 

 eration their horny covering, will enter 2.3 times into the total 

 length of the cranium. The superior aspect of the cranium has a 

 longitudinal, median, shallow furrow that becomes more distinct 

 in the frontal region between the supraorbital processes.^ 



Posterior to the supraorbital processes the frontal region is 

 notably broad, and considerably (sometimes almost double the 

 width) broader than the forehead is in front of the processes. 

 The latter diminishes rapidly in width as one passes anteriorly, 

 and, when the cranium is viewed from above, it is seen that 



1 At this writing I have at hand the skeleton of a specimen of Syr7ihi7n nebu- 

 losunt, a " bird of the year," collected by me at New Orleans, La., in July, 1883. 

 In it the furrow, as usually seen in owls on top of the cranium, is replaced by a 

 sharp, linear, deep-seated crease that is distinctly carried from the base of the 

 superior mandible to the supraoccipital prominence behind. — R. W. S. 



